Flow-controlling device



Jan. 7, 1930. c'. s. BROWN 1,742,846

FLOW CONTROLLING DEVICE T Filed-Sept. 4, 1920 3 Sheets-Sheet l 3Sheets-Sheet` 2 c. s. BRowN FLOW GONTROLLING DEVI CE Filed Sept. 4. 1920nlillonltillrlllunllrln nnllsulnflv Jan. 7 1930.

Jan. 7, 19.30. C. s. BROWN 1,742,846`

FLOW CONTROLLING DEVICE Filed Sept. 4 1920 3 Sheets-Sheet 3 Hl lHl ./pa.Srta/muts Patented Jan. 7, 1930 UNiTED STATES PATENT OFFICE? i CHARLESS. BROWN, OF`NASHVVILLE, TENNESSEE; CHARLES H. SIMPSON, EXECUTOR QF SAIDCHARLES S.. BRO'NN, DECEASED, ASSIGNOR T0 CHARLES H. SIMPSON, DAN E.INICGI'UFGIN,` AND CHARLES C. TRABUE, TRUSTEES FLoWboNtrnoLmNe DEVICEApplication Ied September 4, 1920. Serial No. 408,247'.

'i' means for automatically releasing and dis-y continuing the liquidsupply to the individual tanks.

Another object of invention is toy pro` vide ainetering device forliquids which; comprises a, plurality of tanks and which isprovided withmeans acting upon the rise of liquid level in one of the tanks torelease a liquid supply to another'tank, a further object being toprovidemeans fordiscontinuing thefliquid supply toa giventank: when theliquid level thereinV attains the given poi-nt.

Another objectief my invention is to provide metering devices forliquids comprising a tank having an outlet provided with an air chamberand having means operated by air- 'from said chamberl for the releasingand discontinuing of the flow of liquid from the source of supply to thetank.

Another object of my inventionisto pro-` vide a metering device forliquids comprising a plurality of tanks and including means foralternately releasing asourceof` supply to one tank and discontinuing asourceof supply to the other tank so that one tank may drained whilethe' other is being iilled'.

Another object of my invention is to provide a metering device forAliquids comprisingA a plurality of tanks the source of supply to whichis 'controlled by air from air cham-4 bers in outlets of the tanksl andalso by the.

dynamic force of liquid in the tanks.y

Another object of my invention is to provide a metering device fiorliquids :comprising a plurality of tanks-having inlets which may he airlocked and outlets which may bev air locked in which the air locks ofthe inlets are'controlled by means of the air from the air locksof theoutlets, a further object being to discontinue the supply to a giventank and release the supply to another tank bythe action of air from theoutlet'of the given tank.`

A further object of my invention is to pro'-` vide a device embodyingany of the other objects of my invention in which' the admission of airto the air chamber of the outlet and'its withdrawal therefrom for thepurposes stated also control the tankoutlet. 5 Y j Other and further objectsfof my invention will appear fromthe following description taken inconjunction with the accompanying drawingsforming a part of thisspeciiication and will be pointed out in the hereunto j appended claims.y

In the drawings in which like characters indicate similar parts, Figure1 vis a verticalv sectional view of a metering device embodying myinvention. Figure2 is arvertical, sectional view of a modification of adetail which be substituted in the device shown in Figure 1. lFigure 3is a vertical, sectional' view of a modiiied deviceembodying myinvention. Figure 4 is a top plan View of? the device shown in Figure 3.Figure is a ver- Y tical section of' a simplified modification.

Referring to Figure 1 for the purpose of describing the kgeneralfeatures of my vinvention, it will be seenthat there are two tanks,

i 1 and 2, which, for thepurpose of metering liquids, may be o'f knowncontent; and the content ofi these tanks may-'be altered by ad-r justingupwardly and downwardly the displacing members 1 and 2', such adjustmentbeing provided for in any manneras by the bolts 60 moving with members 1and 2 and passing through slots'61 in the upward extension 22 of the'tanks 1 and 2, the members 1f and 2 being clamped in desired positionbynuts @2L The sour-ceci supply for the tanksv 1 and 2 is theinletopening 9 and the final outlet is the' pipe 35 leadingfrom the casing23A-into which the tanks discharge as hereinafter described. In orderlthat the` amount of liquid flowing' out of the pipe 85 may be known, thetanks 1 and 2 are alternately filledand drained and a iioatBZ. whichactuates a counter 31 is providedto keep tall of the number of timesthetanks are filledv In order to leffect the'ralternatey filling anddraining of the tanks, Il provide means for controlling the flow ofliquid from the source, This means consists 9 to each of the tanks. of acircuitous passage including the chamber A A which is made up byinserting in 'the tank 8'the partition 10 which extends from the top toa point short of the bottom thereof,

the partition 12 which extends from the bottom of the tank 8 upwardly toa point short of the horizontal partition 14 from `whichhorizontalpartition there extends downwardlly a partition 13. Each sideof the tank 8 isv I source of supplyl to one of the tanks air is forcedinto the chamber A through the pipe 33, all Y as hereinafter described.

In order to control the discharge of each of the metering tanks Ilprovide means which will prevent outflow'therefrom until -the liquidtherein has reached a predetermined leve This means includes a pipe 17extending upwardly into the tanks' 1 and v2 and provided with/thedownward extension 18 and an upward extension 18. v Fitting freely overand spaced from each of the pipes 17 is a bell 18 which is open at thebottom and closed at thel top except for the passage therethrough, ofsmallV pipes hereinafter described.

When the air has been permitted to escape f fromthe chamber A leading'tothe tank 2 as shown in the righthand side of Figure 1, liquid coming inat the passage' 9 will fiow through the circuitous passage formed by thepartitions 10, 12, 13 and 14 and the end wall of the tank 8 outwardlythrough the notch 15 and into tank 2. The liquid level willthen rise inthe'tank-2 until it closes the bottom of the bell 18 therein but'the airis confined in this bell 18 andrinthe piper17 because the last previousoperation has leftsthe loop of pipe formed by the pipes 18 and 18 partlyfilled withliquid; yand the pipe 23 leading from the'bell 18 throughftheloop 23 and di-;y

viding into the branches 24 and 25 lis also y, closed by the presence ofliquid in the loop 23"" which collected duringthe time when the liq-Vuid was flowing into the tank 1. *And furthermore the pipe V27 leadingfrom the topV ofthe bell 18 through the loop 33 to the pipe 33 whichopens between the partitions 10 and 12 is sealed bythe liquidV in theloop 33. VAs the Vlevel rises Y'in the tank 2 it will be seen therefore,that. the head of liquid acting upon lof the tank 8 into the said tank1.

In Vorder to release the the air in bell 18 will increase and when thehead of liquid X is equal to or greater than the head of liquid X theair vconfined in the A at theleft ofFigure 1 will escape and the sourceof supply will be released to tank 1 so that the liquid will fiow fromthe pipe 9 through the circuitous passage at the left side The liquidcontinues to flow into tank 2. It is also to be noted that some air hasescaped from the bell 18 during the blowing out of the seal23` at theleft of tank 8 and during the time the liquid is rising in bell 18 toseal the lower end of pipe 23. This escape of air permits a rise ofliquid in bell 18 with a Vconsequent fall of liquid in tank2 so that theliquid acquires a dynamic force which acts with the liquid head X andcompresses the air in the bell 18 until its pressure may be great enoughwhen transmitted through the pipe 27 tothe loop 33 to blow out ofthatloop or trap the liquid which previously sealed it and force air into,the chamber A at the right side yof tank 8, thusair-locking anddiscontinuing the source of supply into the tank 2.

in tank 2 released the source of supply into the tankl and discontinuedthe source of sup- Thus it will be seen that the rise of ply into tank 2and that this operation has been brought about bythe air contained inthe discharge passage of the tank 2 and that the dynamicV force in theliquid in said tank may also'be utilized. Now that the air has beenreleased from the bell 18 in tank 2, theV liquid will riseoutside of thepipe 17 and flow intothe top thereof and out through the pipes 18 and 18so that a siphon action is initiated and this Siphon action willcontinue vuntil the level in tank 2 drops below the bell 18, whereuponair will bubble up into bell 18 breaking the siphonand theliquidcontained in the bell 18 will dropV downinto the bottom of thetank 2. In order to discharge this residual liquid, I provide anauxiliary siphon V60, adapted to discharge practically all the liquidVfrom the'tank 2 after themain .Siphon discharge is no longer operative,insuring thorough sealing of the outlet.

the discharge pipe 17 may have'outside of it Vpipe 61 and inside of itpipe 62 joined to- Instead of providing siphon tube 60 thef bell 18 maybe made as shown in Figure 2 and v form a siphon leadingfto the pipe18". VSuch Y all of the liquid which settles down into the bot-tom ofthetank after the air'startsto Va. construction would carry awaypractically sof bubble under the edge: of the bell 18. Itis also; to benoted that pipe 62 providesv an yair pas sage from the outlet pipes tothe interior oi the bell 18 from which the air escapes by the pipes 23and 27 as above described and for cess of air supplied to the .chamberAwillV bubble under partition 10 instead of throw'- ing out the liquidbetween the partition 13 and the end wall of the tank 8 which mightresult in preventing formation of an air lock in chamber A if the headof liquid above the lower edge of the partition 13 was so reduced as tolbe less than the head of liquid above the lower edge of partition 10.

It is also to be noted that the length of the loop 23 can be soproportioned as to effect the releasing of the supply to another tankwhen the level in a given tank reaches a. predetermined point. Y

It. will be obvious from the above descrip` tion that the air whichlocks the discharge is used for locking and unlocking the inlet ordiscontinuing. and releasing the source of supply to the diiierent tanksand that the air in the discharge passage of'one tank unlocks the inletto another tank and later or simultaneously locks the inlet to the firsttank.

There may be a small interval of time from the releasing of the iiowinto tank 1 and the discontinuing of the flow into tank 2 until thebeginning of the discharge from tank 2 for two reasons. First, becausethe head of liquid in tank 2 falls slightly in fillingy up that portionof the discharge siphon head or bell 18 which has been emptied of air inthe action of starting the flow into tank 1, 'and second,

because the seal in loop 33 may have a higher head than the seal in loop23. During the period in which the liquid level is again rising in tank1 the supply may be flowing into both tanks but this` interval may bemade as small as desirable by careful adjustment of the heads oftheliquid seals in L loo s 23 and 33 and b takin advantage of p a y i9; a:

have' a great enough head te withstand the greatest pressure which isnecessary within the discharge Siphon head, namely,v the. pressurenecessary to blow the liquid out of the loop 33 and lill the chamber Awith air to lock the liquid inlet to one of the tanks.

When-a bell of lesser height suchV shown in Figure 2 is used, thedischarge loop 18e must have a greatv enough sealing head to retain theair in the more deeply submerged bell 18 and the loop 33" will have tobe proportionately longer.

After the air under pressure in bell 18 has blown the liquid seal out ofloop 33 and" lilled achamber A with air to discontinue the supply to oneof the tanks it; is necessary that the loop 33 be re-illed with liquidtoprevent the air from escaping from chamber A or being withdrawnprematurely by the vacuum formed in bell 18 as the liquid head drops inthe tank. This may be accom-V plished by expanding the top of pipe 33out into a cup 37 or by positioning the end of pipe 33 below the minimumliquid level be! tween partitions 10 and 12 as shown in Figure 3,hereinafter described. Air will force the liquid up into cup 37 andbubble up' through it without throwing it out and the liquid will thenrun back into loopz33 and seal it.

In the device shown in Figures .3 and 4 the saine general constructionand operation is found with certain modiiications: The. pipe 27 isprovided with an auxiliary opening 28 so that the liquid will risewithin the bell 1'8 and on the outside of the pipe 17 luntil the levelreaches the lower end of a larger bell 19 which surrounds the upper endof the discharge siphon formed by the pipe 17 and the bell 18.' Thisbell 19` also surrounds the auxiliary opening 28. lVhe-n the liquidreaches the lower edge of the bell 19, air is trapped therein becausethe seal in the loopV 23 prevents escape throughv the pipe 237 the sealin loop 33 prevents escape through the pipe 27 and the seal in thedischarge pipe 18 prevents escape through the pipev 17.. When the head Xequals or exceeds the head X ythe seal in loop 23"will be blown out andthe escape of air from the chamber A permitted as above described forthe purposes stated. rlhe air will escape until the level reaches thelower end of the pipe 23 and seals it. The

liquid thus rises in the bell 19 and Vdrops inV the tank 2 so that thedynamic force of the liquid assists the pressure within the bell 19'Vwhich is increasing as the level rises inthe tank 2 to blow out the sealinthe loop 33 for the purposes above stated. The'bell19 seals the upperend of the discharge Siphon preventing the entrance of air through theopening 28 and the discharge siphon begins tov operate.V When the leveldrops `down below the edge of the bell 19 the air would enter theopening 28 and passinto the top of the leey ' ing 28 to break thedischarge. siphon.

portion of pipe 27 containing openings 28Y in an outlet .passage effectsanV opening of* Vthat passage.' v f p l Inasmuch as my inventionincludes the idea i in the loop 33 is so adjusted that a `riseof' liquidwithin the tank 2,'for example, will. f compress the air within the bell18 and the 60j discharge head but the pipe 27 is extended4 down to apoint below thelevel of the lower edge of thevbell 18 and iswater-sealed and therefore no air will pass'through the openmay beomitted and the bell 1.8 otherwise supported, for example as shown inFigure 2.`

The tanks 1 and 2 may be made with conical ends as shownin Figure 3 sothat slight changesy in contents will' produce f great changes in head.In addition the upper endsV of-the tanks iin the construction shown inFigures 3 and 5 have positioned within them auxiliary tanks 20 which areso large as to leave little space between them and the walls 22 of thetop end of the tanks. Y The supply to each tank flows into theseauxiliary tanks 20 and thence into the main tanks 1 and 2.A In order tocatch and restrain for a short period the first liquid passing out oftank 8 after the supply has been released to one of the tanks 1 or 2 soas to prevent flow of liquid into a tankbefore it is entirelyemptied,and in order to compensate for any differences of content of the tanks 1and 2 to secure It will be obvious from the foregoing thatv I haveprovided a metering device in which a plurality of tanks are alternatelyfilled and the filling of one tank effects the release of the -supply toanother tank and cuts ofl` the supply to the filled tank'by the actionof the air in the chamber of the discharge passage and that the dynamicforce in the liquid brought about by one operation of the air is:yutilizedY in another operation, and that thev use, to perform theseoperations, of the air of adjusting the height of head'in the liquidseals in the loops 23 and 33 it will be apparent upon inspection ofFigure 1 that open! ing and closing of the inlet air lock and openingthe outlet air lock can all be effected by pipes 27 and 33 by properadjustment of loop- 33. VIn this casethe height of the liquid headoutlet pipe 17 untilthe head X exceeds the head K whereupon the liquidwill be blown out ofthe loop 33 and air will then .pass into the chamberA at the right handend of the tank 8fand discontinue'the supply to tank2. The liquid in cup 37 runs back into the loop The 33 to 4seal itand'prevent escape of air'from chamber A by reason of the pressure vofliquidi in tank 8 or by reason of the vacuum formed in the bell 18 asthe liquid level in the filled tank falls. The air having passed out ofthe bellv 18 and the pipe 17 liquidwill rise within the bell 18 and passinto the pipe'17 and initiatethe discharge after the supply has beendiscontinued by the' filling of the chamber A with air.. As thedischarge continues and the level in tank 2 drops the vacuum exist- .Ying in the top of the discharge siphon formed' by the bell 18 and thepipe 17 will increase and just before the tank is emptied far enoughtopermitair to pass under the edge of the bell 18 the vacuum will beamaximum and the length of the loop r33 may be adjusted so thatY underthe action of this maximum vacuum the air will be `Withdrawn from thechamber A and release the fiow into the tank 2 when head Z exceeds headK.

24 and 25 and the loop 23which also may be used for withdrawing air-fromchamber A and which are essential in securing the alL ternatefilling and emptying of tanks 1 and 2, above described, may be dispensedwith inV lthe performance of the mode ofoperationy of a single tank-lastdescribed and in Figure The construction shownf in Figure 1 may be soadjusted as to carry'Y out this mode of operation. The pipes 23,`

5 there is shown a device simplified by the j omission of these parts.yIn order that the' filling oftank 2 may not commence before thedischarge is complete, anl intermediate tank 20 is positioned betweenthe tank 8 and the tank 2 which will catch and hold `the first fiow fromthe tank 8 because it has been partly V emptied during the dischargingof tank 2'by means of the siphonV 21 as above described. In vtheconstruction shown in Figure 5 and above described, only a single tankis necessary but any numberY of tanks may be supplied from supply tank8and any number of tanks may discharge into a 'common `discharge tank34.' Y

that my inventionis defined by the claims ap- Y pended hereto.

c 110l While I have described myjinventi'on -inr connection withspecific embodiments thereof,v

Y it is to be understood that I am not limited.'

to the particular constructions described but Having described myinvention, whatI t claim as new and desireto secure by Letters Patentis:

1. In a device of the'character described, a plurality of tanks, meansfor 'separately supplying-liquid to each ofsaidtanks, an;

outlet for one of'V said tanks and'having a liquid-sealed air chamber,and meanswhereby the air in said chamber initiates lflow from saidliquid supply to'another of said tanks upon ythe filling toapredetermined pointV ofsaid tank having said chambered outlet.'V

2. In a device of the character described, a plurality of tanks, .meansfor separately Firrita-sire vsupplying liquid `to each of "sa-id tanks,an outlet for one of said tanks `.and having a liquid-sealed airchamber, and means whereby -the air in said chamber .controls the liquidVsupply :to a yplurality of :said'tanks upon the lling'to apredetermined point of said :ta-nk having said ychambered outle't.

8. In a idevice of the `character described, .a iplura'lity fof tan-ks,Ymeans for separately :supplying liquid .to each .of'gsaid tanks, .anloutlet for one voi? said tanks and ,havin-ga liquid-'sealedairfchamberyand means whereby the air in -said chamber discontinues the'liq- .uid supply to one :oisaid tanks and releases fthe liquid supplyvvto yone of said 'tanks upon the till-ing to a predetermined gpoint-oif :said 'tank having said fcham'bered outlet.

4. yIn a device of the character described, fthe combination of aKplurality of tanks, 'means for fsupplyingliquid tothe inlet oat 4saidtanks, and inlet andan outlet for each `of said `=tanks, a liquidsealedlair lchamber in {ea-ch inlet in :each Joutlet *for controlling flowtherethrough, `and mea-ns whereby the lair from the fair ehamber in theoutlet vof one rtank 'may .be :utilized to :unlock theseal of thechamber 'ofthe inlet 'of another tank .and to controlling dowtherethrough, and .means `conducting .the air from the air Vchamber fof'the outlet 'of each container #3o 'the air echam- Iber r.ci the .inletfoi both scontainers, and whereby up on the :filling With liquidfofeither of said containers,th'e outlet ofssaidcontainer .and the inlet:of the :other container :are

.opened .and :the inlet of `the ifilled vcontainer' iis closed.V

f6. In combination, :a tank, a liquid `supp-ly yinehiding .alliquidesealed Vv.air .chamber stoi- :controlling flow therefrom, fa:si-phon outlet .including a liquideseal'ed 4.air chamber `forcontro-lling flow therethrough, `means 'for introducing yair into, andwithdrawing it from lsaid chambers andv imeansjbetween 'said inlet andsaid tank for preventing .mixture of 'incoming liquid with 'outgoingfliquid .ii the :air is drawn from sai-dri-nlet chamber `beforedischarge is complete.

'7. In combination, .a Stank, a liquid supply linclud-ing aliquid-sealed sair chamber for vcont-rolling -iovv therefrom, a -si'phonyfoutlet `including a liquid-sealed fair Velrandber for controlling"flow therethrough, :and :a single 4means `for transterringair from.said'ou'tlet fchamb'er to :said "inlet :chamber .and fior introducingfair into :said outlet chamber.

8. In va :device of the ch-araoter described, a plurality of tanks,.means fior .separately .sup lying 'liquid .to {each fof saidfitanks,.an out et lfor one off .said tanks, la 11i' u-idesealed air@ halmzherin fsa-id Outlet s' i. stantially immersed when said -tank .is dull, andmeans 1whereby air itromsaidfcha'mber and dynamic foreex'of liquid :dueto replacement of air in Vsaid chamber by liquid 'discontinues :the

supply 4toliqufid :to said tank having-said'out- .having an -aifr :trapto control :flow "of liquid:

therethrough., Vand a pi-pe leadingffromtheair space of one .oit fsa-idtraps to :the air space-'of "the otherfand'havingfa liquid seal :betweenvits :ends ttor :controlling :flow of air .therethrough .and said "sealV:bein g provgi ded with :aye-nt and subject .to 'the ilpfress-ureofithe air in saidfoutlet air trap, whereby :the `air in the :air trap-of sai-d passage is y'vented lwhen `the ,liquid in 'said container:reaches fa predetermined level.

10. In a `:de-viceof :the :character described,

afcontainerfhaviing an ioutlet provided with a liquid-sealed vair:chamber 'controlling rflioiw 'oit liquid therethrough, a liquid conduit'having :a iiquizdeseafled air chamber controlling -iow of :liquidtherethrough, a pipe rhawing a `liquid seal .for 'controlling flow ofair therethrough, and a :vent `leading yfrom A'said ,pipe :and Vno1'-'mally sealed by thel liquidwof fsaid sseal.

il. In a ldevice of .the character described,

:a plurality rof tanks, inea-ns .or'fseparately supplying liquid 'toeadh :of :said taks, an outlet .for one fozf fsaid tanksvand having aliqeu idese al'ed air y'chamber :and nieans'whereby :air in :said airchamber Idiseontimi'es the liquid supp-ly .fte the tankhawiing' saidoutlet let :for-.each :offsai'd tanksfand 'having :a liquidsealed airchamber for controlling ilow fot liquid therethrough, land ineenswhereby fthe .fair einem fsa'id 'chamber fof fa first (one olf saidrtanks V.initiates .low ffroin said 'liquid Lsupply lto anotherfof ysaidrtariks when the liquid fin `said iirst onel of :said tanks reaches faIpredetermined l'euel, andineans -vwhereby fair `from -th'e airfcharnber yof `said other foi Asaid -ta'rks -'discontrinues the flowoi-'fsaifdfliquidsupply v'to :said other Stank when lthe liquid .in saidother tank vreaches `a predetermined Ilevel.,

a 'deviceoi the character described, .a plurality of tanks, means Yforseparately .supplyingiliquid to eaehot's'aid tanks-,an eut-v let lforone of said tanksfand having `ali' uidse'aled aireliaruber therein fioreon'trol ing :unweit iig-uid therethrough, means im: ne

aso l leasing air from the air chamber'in said outlet and therebyunlocking the seal of the chamber of said outlet when the liquid in thetank containing said outlet reaches a predetermined level, and meanswhereby air -so withdrawn initiates V flow from said'liquid supply toanother of 'said tanks, upon thefilling to a predetermined point of saidtank having said chambered outlet.

14.- InV aqdevice of the character described,

Ythe ,combination 'of Y a plurality of tanks,

-means Yfor supplying liquid `to the inlet of' said tanks, an inlet andan outlet for each of said tanks, a liquid-sealed chamber ineach inletand in each outlet for controlling liow therethrough, means forreleasing air `from Y the air chamber in the outlet of a irst one ofsaid tanks and thereby unlocking the seal of the chamber of said outletwhen the liquid in said first one' of said tanks reaches apredetermined'level, and means whereby air so released may be utilizedto unlock the seal of each of said tanksa liquid-sealed air cham- Y berin Yeach inlet and in each siphon outlet -for controlling flowtherethrough, and means whereby theair from the air chamber in theSiphon outlet of each tankv may be utilized to unlock the inlet seal ofanother tank and to` lock the inlet seal of that tank.`

16. In a device of the character described, a plurality: of tanks eachhaving an inlet and an outlet, a liquid-sealed air chamber in each inletfor controlling flow therethrough, a liquid-sealed air chamber in eachoutlet for controlling flow therethrough and subject to themaximum headof liquid in its tank, liquid-sealed vents for said air chambers of saidinlets, pipes fromgthe air chamber of the outlet of each tank to the airchamber .of the inlet thereof,and pipes from the air .chamber of theoutlet of each tank to the vent of another tank. e

17. In a device of the character described, a plurality of tanks eachhavin an inlet and an outlet, a lliquid-sealed air c amber in each inletfor controlling flow therethrough, a liquid-sealed air chamber in eachoutlet for controlling' flow therethrough and Subj ect to the maximumhead of liquidin its tank, liquidsealed vents for said air chambers ofsaid inlets, ipes havingVliquid-sealed traps and connectingy the airchamber of the outlet of each tank to the air chamber of the inletthereof, and pipes from the air chamber of the outlet of each tank tothe liquid seal of the vent of another tank.,

18. In combination, a tank, a liquid inlet therefor havingl aliquid-sealed air locking chamber for controlling flowfofliquidtherethrough, an outlet for said tank and having la liquid-sealed airchamber for controlling aus saidtank and sealedby'and subject toz the Ahead of liquid therein, anairpipe leading from the air space'of saidbell to the 'air space of said chamber and having a liquid seal b etweenits ends, avent leading from said seal at a point below the normal levelof liquid therein, whereby said vent is sealed bythe liquidof saidseal.V

20. In a device of the class described,ra

tank, a liquid conduit for,V supplying liquid to said tank and having anair-'locking cham# ber for controlling ilow of liquid therethrough, aSiphon outlet having a liquid trap to prevent flowofair fromwsaidoutlet,'an

' airrpipe leading from the upper part offsaid 1V Siphon outlet to theair space of the air-lock-V ing chamber of said supply conduit and havf,

ing a liquid trap therein to control flow of air therethrough and beingotherwise closed. 1

21. In combination, a liquid container, an z outlet for ,said containervhaving a liquid-y sea-led airchamber for controlling flow of liquidtherethrough, lazsource of liquid sup` ply, a liquid conduit leadingfrom said source,

and means whereby the air'in saidl chamber initiates flow of liquidthrough said conduit upon the fillingrto a predetermined pointlof saidcontainer having said chambered outlet.

22. In a device of the character described, a plurality of meteringtanks, liquid inlets for each tank and havingair controlled opening vandclosing means, an air bell in'leach of said tanks and subjectto themaximum head of liquid therein andsealed by said liquid, means wherebyair from each bell may be utilized to close the inlet ofits tank when'liquid attains a predetermined level therein, and

ltains a predetermined level. l e

23. In combination, atank, a liquid con-A duithaving an air-'lockingchamber to control liquid flow therethrough, an air bell 'in said tankand sealed by and subject to the head of liquid therein,an air pipeleading lfrom the air space of said bell and open at its end and havinga liquid trap to control escape of air therethrough, and a vent pipeleading from the air space of said air-locking chamber to a point belowthe liquid level Vof that side of said liquid trap which is open to theatmosphere, whereby'said vent is normally sealed y liquid in said liquidtrap.- 24. In combination, a tank, a liquid conduit having anair-locking chamber to control liquid flow therethrough, an air bell insaid tank and sealed by and Isubject to the head of liquid therein, anair pipe leading from the air space of said bell and open at its end andhaving a liquid trap to control escape of air therethrough, and a ventpipe leading from the air space of said air-locking chamber to a pointof said liquid trap which is below the liquid level therein, wherebysaid vent is normally sealed by liquid in said liquid trap.

25. In a device of the character described, the combination of aplurality of tanks, means for supplying liquid to the inlets of saidtanks, an inlet and an outlet for each of said tanks, a liquid-sealedair chamber in each inlet and in each outlet for controlling flowtherethrough, and means whereby the air from the air chamber in theoutlet of each tank may be utilized, thereby unlocking the seal of theoutlet thereof, to unlock the seal of the chamber of the inlet ofanother tank and to lock the inlet seal of the tank of which the outletseal is unlocked.

26. In a device of the character described, the combination of aplurality of tanks, means for supplying liquid to the inlets of saidtanks, an inlet and an outlet for each of said tanks, a liquid-sealedair chamber in each inlet and in each outlet for controlling flowtherethrough, and means whereby the air from the air chamber in theoutlet of each tank may be utilized to lock the seal of the chamber ofthe inlet of the same tank and to unlock the seal of the chamber of theinlet of another tank.

27. In a device of the character described, two metering tanks, a sourceof liquid supply, conduits leading from said source respectively to eachof said tanks and each having a liquid-sealed air chamber therein tocontrol flow of liquid therethrough, an outlet for each of said tanksand having a liquidsealed air chamber for controlling flow therethrough,an air pipe from the air chamber of each outlet to the air chamber ofthe inlet of the same tank and having a liquidsealed trap therein, aliquid-,sealed air pipe leading from the outlet air chamber of each tankto the inlet air chamber of the other tank, and a vent for the liquid ofthe seal of each of said last named pipes.

28. In a device of the character described,

two metering tanks, a source of liquid supicc

